Method of recovering ammonia from coal-gases and the like.



H. ROTERMUND.

METHOD 0? REOOVERING AMMONIA PROM GOAL GASES AND THE LIKE.

APPLICATION FILED 10120.3, 1910.

Patented July '22, 1913.

I [MENTOR am my; BY m v: 6;;

/1 TTORIVE Y8 WITNESSES: gm?

HERMANN ROTERMUND, OF DUSSELDORF,'GERMANY, ASSIGNOR T ACTIEN-GESELLSCHAFT FUER KOHLENDESTILLATION,

TION OF GERMANY.

OF DUSSELDORF, GERMANY, CORPORA- METHOD OF RECOVERING HMMONII IA FROMCOAL-GASES AND THE LIKE.

Specification of Letters Patent.

Patented July 22, 1913.

Application filed December 3, 1910. Serial No. 595,346.

To all whom it may concern.

Be it known that I, HERMANN Rornn- MUND, a subject of the, Emperor ofGermany, residing at Dusseldorf, Germany, have invented new and usefulImprove mcnts in the Methods of Recovering Ammonia from Coal-Gases andthe Like, of

which the following is a specification.

My invention relates to the application of positive heat to that portionof the acid chamber which carries the outlet for aqueous vapors andnoxious gases and has for its object to maintain the concentration ofthe,

acid which was in said chamber and of the ammonium salts bycounteracting the tendency of the solution to absorb aqueous vapor. Thisobject is preferably obtained by causing a current of hot air or hotproducts of combustion to pass through the saturater bath or over itssurface.

The process to which this invention generally relates is fully describedin United States Letters Patent No. 969,907, dated September 13-, 1910,to J. A. Roelofsen to which reference is made for the purpose of.

avoiding a complete restatement of that process.

The invention will be clearly'understood from the following description.

The drawing illustrates one arrangement of the apparatus in which myinvention may be carried out, showing particularly the application ofhot products of combustion as passing through the saturater bath.

The hot gases coming from the coke oven, retorts pr other gas makingapparatus are completely cooled in the coolers 1 andZ, therebycondensing the tarry vapors and alsothe aqueous vapor, containing mostof the ammoniacal salts not volatile at ordinary "temperatures, as wellas some volatile amwas-lag" these condensates are collected andseparated in tank 3. The gases to be treated, after having been cooled,pass through a gas pump and a tar extractor 5, which separate theresidual tarry vapors, and without being/reheated, are conducted throughpipe 6 into a lead-lined-saturater 7. Thecondensed ammoniacal liquorfrom tank 3 is delivered, by means of a pump 8, through pipe 9, intoammonia still 10, an alkali, such as li'me, is also introduced, theammonia thus liberated passes through pipe 13 with or .th

tend that the arrow facing the pipe 20 is without super-heating intosaturater 7.

applied in any other suitable manner.

monium salt contained in the saturater 7.

The gases of carbonization enter into one of-these compartments, throughthe perforations in the end of pipe 6, pass up through the acid solutionand leave the saturater, after having thus been freed from all ammonia,by means of pipe 17. The vapors from the ammonia still 10, enter theother compartment 2 1 of the saturater 7, through the perforated end ofpipe 13. The aim monia contained in these vapors-is thereby absorbed,while the aqueous vapor and gases which may contain hydrogen sulfid,carbonic acid and other noxious compounds, pass out of the saturater,through pipe 18. Into this chamber 24 of the saturater is introduced, bymeans of pipe 20, blower 21 and inlet pipe 22, a current of hot air ortroduced below the surface of the bath through-the head 23 as shown inthe drawing, or may impinge on its surface or be In this way byregulating the quantity of hot air or'productsof combustion, by means ofblower 21, the concentration of the bath maybe kept at any desired pointand thereby prevent a lowering of the concentration of the acidsolution, which would prevent the ammonium salt from separating in thesolid state. The ammonium salt is removed. from the saturater by meansof the ejector l9 anchthere is a continuous fresh supply of sulfuricacid tothe entrance chamber of the concentrator 7 to maintain therein asubstantially constant quantity of liquid.

It is important that when the heating gases are introduced into thechamber 24, either upon'the surface of the bath or below it, that saidheating gases should be free from chemical substances, which might havea tendency to enter into combination with the liquid or affect therelative chemical purity of the solution. Hot air or air containingcarbon dioxid is satisfactory for this purpose. A very convenient andeconomic source of heat is that furnished by the gases (of combustionwhich have heated e oven Walls) and in the drawing I inover from the vstill 10 may have a heat of approxinfately 100C. In order to 11121111"tain the bath in the chamber 24 at a concentration of 2& to 33 Baum, theheating gases entering the said chamber through the pipe '22 will beat200 to 250 C.

Having now described my invention, what i claim is:

1. That improvement in the method of recovering ammonium salts in gasesof carbonization which comprises the introduction of cool purified gasesof carboniZat-ion J into one portion or" an acid solution and thesimultaneous introduction of distilled ammoniacal products into anotherportion otsaid solution and conducting relatively hot gases to andcausing the same to become operativeon that portion of the solutionwhich absorbs the ammoniacal products and maintaining the heat of saidgases during their passage to said solution so that; substantially theirfull heat value will become operative upon said portion of the'solution.

2. The method of recovering of ammonium salts from gases ofcarbonization which comprises cooling the gases to separate therefromthe tarry matter and to condense gases which part of the aqueous vaporcontaining most of the non-volatile ammonia compounds contained in thegases and a portion of the volatile ammonia compounds, distilling saidammoniacal condensate, and then simultaneously introducing said gasesinto one division of a single acid solution of ammonium saltsand intoanother division-the vapors of distillation of the said ammoniacalcondensate together with a separate current of hot neutral as, andseparatelyv leading off the gases 0t carbonization and the noxiousgaseouscomponents of the vapors of distillation together with the saidheating gases, from the saturater.

3. The method of recovering ammonium salts from the gases carbonizationwhich comprises the cooling of the gases and separating therefrom anammoniacal condensate comprising the tarry matter and most of theaqueous vapor containing non-volatile ammonia compounds and a portion ofthe volatile ammonia compounds, and then simultaneously introducing saidgases of carbonization so treated, the vapors of distillation of theammoniacal condensate, and the current of hot neutral gasindependentlyinto a single acid solution of ammonium salts andseparately leading off the gases of carbonization and the noztiousgaseous com-' ponents of the vapors of distillation together with, thegases used for heating.

In testimony whereof, I have hereunto set my hand and seal in thepresence of two subscribing witnesses.

HERMANN ROTERMUND. [L- 8.] Witnesses:

ALFRED HENKEL, lVALTnn Von-sneer.

